1. Field of the Invention
The present invention relates to an image forming method and system, and in particular, an image forming system including an image forming device, such as a copier, a printer, or an on-demand printer of an electronic photographic method or an electrostatic recording method, and a post-processing device for performing post processing after image formation, such as book binding or sheet folding and a control method therefor. In addition, the invention relates to an image processing device incorporated with the image forming system, an image forming device, and a post-processing device, and a control method therefor.
2. Description of Related Art
A print process on a print medium, such as a sheet of paper, includes a number of processes such as a plate making process of making a plate from an original, a press plate process of making a press plate which is actually applied with ink from the plate, and a printing process of installing the press plate to a printing machine for conducting printing. Therefore, it takes much time to obtain the final products. Also, a large number of steps in making the plate and the press plate and in adjusting the printing machine are required, and the cost of equipment for the printing machine itself is extremely high. Thus, the printing of a large number of copies and the reduction in cost performance are essential requirements for minimizing the high cost in conducting printing.
Meanwhile, in recent years, along with the development in information processing technology and printing device functions, digital data created with use of desk top publishing (DTP), etc., can be directly printed by a printer based on an electrophotographic system or the like without processing through the print making process and the press plate process. As a result, it is possible to execute printing for a small number of copies in a short delivery period.
Then, in some cases, these printing devices are provided with post-processing devices such as a finisher, a sorter, a collator (collating device), and a machine for sealed cover creation or book binding. While print attributes for causing these post-processing devices to accurately operate are set to a controller of the printing machine, execution of a series of operations from the printing to book binding at once is beginning to be possible substantially without any manual operation. This technology belongs to a technical field called on-demand printing, in which printing with a small number of lots and printing of direct mails with individual messages printed thereon can be realized at a low cost.
In such a system using the printing devices and the post-processing devices, these devices are generally connected in series, and control sections mounted in the printed devices are connected online to the post-processing devices, whereby all the devices including the post-processing devices are correctively controlled.
However, a contractor of the on-demand printing usually owns a plurality of printing devices and uses an appropriate printing device depending on the number of copies and the printing type ordered by the printing customer. For example, in the case where printing products mixed with color pages and monochrome pages are produced, the color pages are printed by a color printer and the monochrome pages are printed by a monochrome printer. This is because the case of conducting monochrome printing by the color printer costs more than the case of conducting monochrome printing by the monochrome-printing dedicated printer. As in this example, when the final products contain the mixture of color and monochrome printed products, an operator needs take the printed products out of at least one of the printing devices by hand and insert the printed products into the other printing device's printed products. In such a situation where interruption of the printing products is necessary, it is difficult to automatically produce the final products containing the mixture of color and monochrome printed products by controlling the post-processing devices with a control section provided to one of the printing devices.
On the other hand, modes for binding the final products include saddle stitching binding in which a sheet bundle is folded in the center and the folded part is bound with a staple or the like, simple binding in which a sheet bundle is not folded and an end part of the sheet is bound with a staple or the like, and case binding in which a back of a sheet bundle is glued with a binding tape or the like. To cope with the above-mentioned modes, it is necessary to appropriately use a plurality of post-processing devices including a finisher for performing the saddle stitching binding and the simple binding and a case binding finisher for performing the case binding.
Therefore, in the case where a plurality of post-processing devices are connected in series to a plurality of printing devices, respectively, duplication of the necessary printing devices and post-processing devices occurs, thereby leading to an enormous waste in equipment preparation.
In view of the above, when various post-processing devices are shared by a plurality of printing devices, it is useful to adopt offline post-processing devices, which are not connected to the control sections of the printing devices. However, in order to obtain the final products while a plurality of offline post-processing devices are operated in association with each other, setting of print attributes needs to be manually performed for each of the post-processing devices. This operation is bothersome and there is the problem in that erroneous setting may happen.
To cope with this problem, for example, Japanese Patent Laid-Open No. 59-121070 discloses an example in which a barcode corresponding to a print attribute is printed and added on the print product itself by the printing device, and the barcode is read by a barcode reader arranged on a sheet path on the upstream side of the post-process device, thereby controlling the post-process device.
Then, according to Japanese Patent Laid-Open No. 10-198105, a so-called “job sheet” corresponding to a print attribute is printed by the printing device separate from the printed products. Pieces of character information indicating the print attributes and the like and barcodes corresponding to the character information are written on the job sheet. An operator reads a barcode section corresponding to a desired process written on the job sheet by using a handy barcode reader arranged on the post-process device to control the post-process device. In this way, even when an offline post-process device is used, without setting the individual print attributes or the like, it is possible to automatically perform the post-processing operation substantially automatic as the online post processing.
However, in order to obtain the final products while a plurality of offline post-processing devices are operated in association with each other, it is necessary to find out the point at which the post processing for the printed products has been completed in view of the prevention of operational errors. To attain the finding, it is necessary to leave a history of the post processing on the printed products.
On the contrary, the barcodes used in the above-mentioned related-art examples cannot be rewritten, so it is impossible to leave the post processing history on the printed products or the job sheets.
That is, when the print attributes are added on the printed products by way of barcodes as described in Japanese Patent Laid-Open No. 59-121070, the barcodes are left on the final products and a problem occurs in view of appearance. Therefore, the barcodes should be made smaller even if added to the printed products and the information amount to be recorded on the barcodes is accordingly limited. Thus, it is impossible to add high level print attributes like associating information for the plurality of post processings.
Also, according to Japanese Patent Laid-Open No. 10-198105, an operator writes a mark on the job sheet with a pen or the like and then reads a barcode corresponding to the mark with a barcode reader to add print attributes. As described above, this operation itself is bothersome, and also a pen input mistake or a selection mistake of the read-target barcode may be made by the operator.
Incidentally, a technology significantly spreading in recent years is radio frequency identification (RFID) tags (hereinafter, referred to as RFID tag). This RFID tag is structured to be batteryless and data stored in an internal memory of the RFID tag can be read out or written in with an exclusive reader/writer in a non-contact manner. Also, computerization density is extremely high because the memory element is used. Furthermore, a chip with the size of 1 mm or smaller, called “μchip” (manufactured by Hitachi, Ltd.), has also been developed. The chip is high in mountability to various media.
This RFID tag is desirably applied to the control of the post processing.